The aggregate of individual attitudes or beliefs shared by the population regarding how well the president is doing in office is an example of what?

Public Opinion

Explanation:

Public opinion is the collective view on a particular subject bu the majority of participants. The term is an aggregate of the thinking and belief of the majority of the population. The term is mostly used in elections and politics but its approach is wide enough in many other spheres like marketing, consumer spending, etc.

Analyzing what the majority of people think about the work of president is an example of Public Opinion.

"choosing is refusing" means individuals face an opportunity cost with each decision they make. economists state that every decision involves trade-offs. opportunity cost is the least desirable alternative given up as a result of a decision.